<html>
 <head>
  <link href="./leetcode-problem.css" rel="stylesheet" type="text/css">
 </head>
 <body>
  <div class="question_difficulty">
   难度：Medium
  </div>
  <div>
   <h1 class="question_title">
    62. Unique Paths
   </h1>
   <p>
    A robot is located at the top-left corner of a
    <em>
     m
    </em>
    x
    <em>
     n
    </em>
    grid (marked 'Start' in the diagram below).
   </p>
   <p>
    The robot can only move either down or right at any point in time. The robot is trying to reach the bottom-right corner of the grid (marked 'Finish' in the diagram below).
   </p>
   <p>
    How many possible unique paths are there?
   </p>
   <p>
    <img src="https://assets.leetcode.com/uploads/2018/10/22/robot_maze.png" style="width: 400px; height: 183px;">
    <br>
    <small>
     Above is a 7 x 3 grid. How many possible unique paths are there?
    </small>
   </p>
   <p>
    <strong>
     Note:
    </strong>
    <em>
     m
    </em>
    and
    <em>
     n
    </em>
    will be at most 100.
   </p>
   <p>
    <strong>
     Example 1:
    </strong>
   </p>
   <pre>
<strong>Input:</strong> m = 3, n = 2
<strong>Output:</strong> 3
<strong>Explanation:</strong>
From the top-left corner, there are a total of 3 ways to reach the bottom-right corner:
1. Right -&gt; Right -&gt; Down
2. Right -&gt; Down -&gt; Right
3. Down -&gt; Right -&gt; Right
</pre>
   <p>
    <strong>
     Example 2:
    </strong>
   </p>
   <pre>
<strong>Input:</strong> m = 7, n = 3
<strong>Output:</strong> 28</pre>
  </div>
  <div>
   <h1 class="question_title">
    62. 不同路径
   </h1>
   <p>
    一个机器人位于一个
    <em>
     m x n
    </em>
    网格的左上角 （起始点在下图中标记为&ldquo;Start&rdquo; ）。
   </p>
   <p>
    机器人每次只能向下或者向右移动一步。机器人试图达到网格的右下角（在下图中标记为&ldquo;Finish&rdquo;）。
   </p>
   <p>
    问总共有多少条不同的路径？
   </p>
   <p>
    <img src="https://assets.leetcode-cn.com/aliyun-lc-upload/uploads/2018/10/22/robot_maze.png">
   </p>
   <p>
    <small>
     例如，上图是一个7 x 3 的网格。有多少可能的路径？
    </small>
   </p>
   <p>
    <strong>
     说明：
    </strong>
    <em>
     m
    </em>
    &nbsp;和
    <em>
     n
    </em>
    的值均不超过 100。
   </p>
   <p>
    <strong>
     示例&nbsp;1:
    </strong>
   </p>
   <pre><strong>输入:</strong> m = 3, n = 2
<strong>输出:</strong> 3
<strong>解释:</strong>
从左上角开始，总共有 3 条路径可以到达右下角。
1. 向右 -&gt; 向右 -&gt; 向下
2. 向右 -&gt; 向下 -&gt; 向右
3. 向下 -&gt; 向右 -&gt; 向右
</pre>
   <p>
    <strong>
     示例&nbsp;2:
    </strong>
   </p>
   <pre><strong>输入:</strong> m = 7, n = 3
<strong>输出:</strong> 28</pre>
  </div>
 </body>
</html>